Many current vehicles employ resilient clips to secure various components to the vehicle body. One such application concerns assist handles that mount to the roof of the vehicle above the doors. Such assist handles serve not only to provide occupants with a convenient point to grasp during ingress to and egress from the vehicle, but also enable occupants to stabilize their upper body during operation of the vehicle. In order to serve these functions, it is necessary for such assist handles to withstand loads of upwards of 250 pounds force without pulling away form the anchor points in the sheet metal of the vehicle.
During assembly of the vehicle, it is conventional procedure of the entire headliner assembly to be installed onto the interior roof of the vehicle in a single operation. In other words, the headliner assembly, with the assist handles and other roof mounted components already attached, is passed through either the windshield or backlight opening of the vehicle body on the assembly line and then the headliner assembly is secured by line operators to the interior roof of the vehicle. In order to accomplish this assembly task, the headliner assembly is typically equipped with numerous fasteners, located around the periphery of the headliner assembly as well as at predetermined locations around the interior area of the headliner, that are adapted to penetrate through corresponding holes located in the reinforcing sheet metal members of the roof. It is the responsibility of the line operators to properly orient the headliner assembly beneath the interior roof of the vehicle and press the fasteners into the various mounting holes in the reinforcing sheet metal members to secure the headliner assembly to the roof of the vehicle.
For aesthetic reasons, the headliner fasteners are typically secured in some fashion to the backside of the headliner so that they are not visible from the interior of the vehicle after the headliner assembly is installed. Consequently, it is often incumbent upon the line operators to blindly “feel” for the location of the mounting holes with their fingers before pressing the fasteners into the holes from the opposite show-surface side of the headliner.
Due to slight misalignments which can occur between the fasteners and their corresponding mounting holes, some of the fasteners may not be properly seated and secured to the sheet metal. This condition is especially problematic when dealing with the fasteners that serve to anchor the roof mounted assist handles. Because these fasteners must withstand substantially higher removal forces than the fasteners that serve merely to hold the headliner in place, they are typically less forgiving of misalignment problems, which can result in a significant increase in the required insertion force, thus greatly increasing the likelihood of improper installation. Under the circumstances, the removal forces that the fasteners can withstand before separating from the sheet metal are greatly compromised.
Accordingly, there remains a need in the art for an improved fastener having a relatively low installation force and a relatively high removal force that is relatively more tolerant of misalignment problems. Ideally, the fastener should be inexpensive to manufacture, reliable and simple to install. Furthermore, the fastener should be particularly adapted for securing structures to one another in a manner which minimizes vibration and the concomitant noise problems that are often associated with such fasteners.